The National Guard Deployments: What's the Legal Basis, and How Do They End?

THE QUESTION

Over the past year, federalized National Guard troops showed up in Los Angeles, Chicago, Portland, and other cities, citing threats to federal personnel and property during immigration-enforcement protests. Governors and courts pushed back hard. What was the actual legal basis, and what happened to it?

WHAT WE KNOW

Normally, the Posse Comitatus Act bars the military from domestic law enforcement, with narrow exceptions, the best-known being the Insurrection Act, which the administration didn't invoke here. Instead, it relied on a lesser-known statute, 10 U.S.C. § 12406, arguing federal property needed protection and regular forces couldn't handle it.

Courts pushed back at every turn. A federal judge found the Los Angeles deployment violated Posse Comitatus because troops were doing law-enforcement work, arrests, traffic control, crowd control, the statute doesn't allow. Another judge ruled the administration lacked authority to federalize Oregon's Guard. In the Illinois case, the Supreme Court itself weighed in: the administration hadn't shown it was actually "unable" to enforce the law with regular forces first, a key precondition the Court said wasn't met. After that string of losses, the administration announced on December 31, 2025 that troops would leave Chicago, Los Angeles, and Portland. In Illinois, the 60-day federalization window had already lapsed, and no troops ever hit Chicago's streets under it.

This isn't necessarily over. The rulings block this specific approach, they leave two other paths open: deploying active-duty forces under a claim of inherent constitutional authority, or actually invoking the Insurrection Act, which carries its own legal standard (last used domestically during the 1992 LA riots).

WHAT'S MISSING

Coverage at the time swung between "Trump illegally invading American cities" and "Trump protecting federal property from lawless mobs." Both oversimplify. Courts didn't rule that a president can never deploy the Guard domestically, they ruled this specific statute, used this specific way, without first showing regular forces couldn't handle it, didn't clear the bar. That's a narrower, more limited finding than it sounds.

WHY IT MATTERS

This goes straight to federalism and civil liberties, how much power a president has to put troops on American streets over a governor's objection, and what checks kick in when that happens. Legal scholars tracking this closely think the Insurrection Act is the more likely path if the administration tries again.